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HomeMy WebLinkAboutPN_Cleanup Scope of Work Draft_180613_v1.pdfSTEMEN ENVIRONMENTAL, INC. P.O. BOX 3644 LACEY, WASHINGTON 98509-3644 CONTR. LIC. #STEMEEI081J9 Telephone 360-438-9521 Fax 360-412-1225 April 23, 2018 RE: REMEDIAL AND CORRECTIVE ACTIONS PROJECT FOR THE COMMERCIAL PROPERTY LOCATED AT 3400 VALLEY ROAD, RENTON, WASHINGTON. TAX PARCEL # 302305-906 The subject property is composed of 5.65 acres (246,114 square feet) of commercially developed property located at 3400 East Valley Road, Renton, Washington. The King County Assessor’s Office lists the subject property as Tax Parcel # 302305-9067. Based on the review of aerial photos, Polk Street Directories, knowledgeable individuals, and information obtained from the King County Assessor's Office, it appears that for approximately 64 years the subject property has been primarily occupied by an automotive wrecking yard and/or radiator shop. All automobile wrecking yard and/or radiator shop related operations have ceased on the subject property. All disabled vehicles, automotive parts, storage trailers and related equipment have been removed from the property. Currently the subject property and the on-site building are unoccupied. Recent environmental investigations of the surface and shallow subsurface soils on the subject property have confirmed the presence of total petroleum hydrocarbons, volatile organic compounds and MTCA 5 Metals at levels exceeding MTCA Method A Clean Up Levels for Industrial Properties. Primarily the adversely impacted soils are present at depths of 2 feet below ground surface (b.g.s.) or less on most of the property. The contaminated soils plume extends to greater depths on selected portions of the property. Initial groundwater samples obtained, using a truck mounted sampling probe, from selected locations on the subject property confirmed the presence of total petroleum hydrocarbons, volatile organic compounds and/or MTCA 5 Metals at MTCA Method A Clean Up Levels for Industrial Properties. A total of eight (8) groundwater monitoring wells were installed at selected locations throughout the subject property using a truck mounted rotary auger drill rig operated by Licensed Resource Protection Well Drillers. Discreet groundwater samples were obtained from the groundwater monitoring wells on two (2) seasonal groundwater monitoring events. Laboratory analyses results for the discreet groundwater samples report no presence of the contaminants of concern at levels exceeding MTCA Method A Clean Up Levels for Industrial Properties. 2 Based on groundwater elevation measurements obtained in the dryer season (lower groundwater elevations) the direction of groundwater flow is to the west, based on the elevations obtained during the wetter season (higher groundwater elevation) the direction of groundwater was to the northwest. The purpose of the proposed remedial and corrective actions project is to excavate and remove all on-site soils that are adversely impacted by the contaminants of concern and to monitor the positive impacts of these actions on the groundwater and the environmental integrity of the subject property. Scope of Work: Prior to the commencement of activities on selected portions of the subject property/site, all utilities will be properly abandoned as per applicable regulations by an appropriate vendor/supplier. Prior to commencement of any on-site excavation activities a storm water treatment handling plan will be developed as per applicable regulations and a permit will be obtained. Silt fencing will be properly placed around the perimeter of the subject property. 1. Demolition, removal and proper off-site disposal of the all asphalt and/or concrete surface materials. All demolition debris will be transported to an appropriate off-site asphalt/concrete recycling facility. 2. Demolition and removal of an approximately 4000 square foot metal warehouse building. Prior to demolition an asbestos survey and/or abatement project will be performed on the building. The concrete slab will be demolished all metal demolition debris will be transported to an appropriate off-site facility for recycling as scrap metal. All concrete demolition materials will be transported to an appropriate off-site asphalt/concrete recycling facility. 3. Excavation and removal of all reasonably accessible surface and subsurface soils containing total petroleum hydrocarbons (TPH), volatile organic compounds (VOCs) and/or MTCA 5 Metals at levels that exceed MTCA Method A Clean Up Levels for Industrial Properties. All excavated soils will be temporarily stockpiled on-site. All stockpiled soils will be properly tarped as necessary. All soils containing the contaminants of concern at levels exceeding applicable cleanup levels will be properly loaded and properly transported to Waste Management’s Duwamish Reload Facility in Seattle using dump trucks. All soils will be transported under a properly issued manifest/disposal authorization. 3 It is anticipated that 8500 + cubic yards (11,900 + tons) of contaminates of concern contaminated soils will be excavated, removed, and transported to the designated off-site disposal facility. Currently, it is anticipated that will be extended to all of the perimeters of the subject property. 4. An appropriate number of confirmation soil samples will be obtained from the completed remedial excavation floor and sidewalls on a periodic and regular basis as per applicable guidelines. All confirmation soil samples will be analyzed for the presence of gasoline range TPH using method NWTPH-Gx and VOCs using method 8260, diesel fuel and lube oil range TPH using method NWTPH-Dx/Dx Extended, and MTCA 5 Metals using EPA method 6020. NOTE: All laboratory analyses will be done on a 48-hour expedited turn around basis to facilitate prompt characterization of existing on-site conditions so that appropriate corrective and/or constructive actions can proceed immediately. 5. The excavation will be backfilled using suitable imported structural fill materials, that will be mechanically compacted for stability. Compaction testing will be performed by the project’s Geotechnical Engineer. 6. All groundwater monitoring wells located within the remedial excavation areas, that are in areas will be abandoned as per applicable regulations/guidelines. 7. Photographic documentation of all phases of the remediation project. 8. If required, the shallow subsurface soils, present in the WSDOT “Right of Way” - Wetland, will be sampled as on-site conditions permit. The soil samples will be submitted for appropriate laboratory analyses. The results of these additional environmental investigations will determine if additional remedial and/or corrective actions are required. 9. Filing of any required permits and start cards. 10. Documentation of all on-site activities in a Department of Ecology required Remedial and Corrective Actions Report and Quarterly Groundwater Monitoring Reports. 11. A site safety plan will be developed and followed by all on-site workers. A copy of the Site Safety Plan will be on-site during all working hours. Staff will have received a required minimum of 40 hours Hazmat Training. 12. The work area will be properly posted and secured with hazard notification signs barricades, orange hazard fencing, and/or chain link security fencing. 4 13. All on-site work will be performed under permits issued by the City of Renton and under the guidelines set forth in MTCA. Upon the completion of the proposed remedial and corrective actions project, the site will be entered into Ecology’s Voluntary Clean Up Program for the purpose of receiving a, NFA (No Further Action) letter. All materials, tools, machinery and labor needed to perform this job will be supplied by the contractor and or his designated subcontractors. Paul W. Stemen Vice President